Inflammatory bowel disease mimicking granulomatosis with polyangiitis: a case report.

Background: We report a case in which the extraintestinal manifestations of inflammatory bowel disease preceded development of gastrointestinal symptoms by nearly 9 months in the context of an unusual autoantibody panel, mimicking granulomatosis with polyangiitis. This case highlights the intricacies and overlap of autoimmune diseases, and illustrates an interesting clinical phenotype: cytoplasmic anti-neutrophil cytoplasmic antibody positive inflammatory bowel disease with predominantly extraintestinal manifestations. Perinuclear anti-neutrophil cytoplasmic antibody positivity has been frequently reported in association with inflammatory bowel disease, but cytoplasmic anti-neutrophil cytoplasmic antibody positivity is uncommon.

Case Presentation: A 54-year-old African-American man presented to our internal medicine resident clinic at the Johns Hopkins Hospital with several months of systemic inflammatory features: anterior uveitis, auricular chondritis, monoarthritis, fever, and weight loss. He did not have a primary care physician due to lack of health insurance and had been seen in our emergency department several times over the past year. These features fit nicely with a diagnosis of granulomatosis with polyangiitis, especially given positive cytoplasmic anti-neutrophil cytoplasmic antibodies. However, 9 months into his clinical course he developed hematochezia with perirectal abscess and fistula. A colonoscopy with biopsy confirmed a diagnosis of inflammatory bowel disease.

Conclusions: This case highlights the fact that extraintestinal manifestations may precede gastrointestinal symptoms of inflammatory bowel disease for months, which may delay diagnosis if not understood and recognized. It further highlights an interesting disease phenotype that has not been widely reported, but may deserve further study. Lastly, the case stresses the importance of the internist in identifying a unifying diagnosis in a slowly evolving clinical process with the assistance of subspecialists. In this respect, the case is of interest to general internists, as well as rheumatologists and gastroenterologists.